Thread guiding mechanism



Sept. 19, 1950 I M. PEDERSEN 2,523,054

Z THREAD GUIDING MECHANISM Filed May 24, 1945 3 Sheets-Sheet 1 76 g 66 V 15] J84 43 1200 ZZZ INVENTOR MATHI'AS PEDERSEN ATTORNEY p 1950 M. PEDERSEN 2,523,054

THREAD GUIDING MECHANISM Filed llay 24, 1945 3 Sheets-Sheet 2 h Z/1a] 183 66 .INVENTOR MATHIAS PEDERSEN BYZ; t;

ATTORNEY T The-operations of .the looper. and pulleraresuch :that if the loops ofthreadabove 'Patented Sept. 19, 19 50 i v a ama-654" f rHREant-etimiNG MECHANISM" Mathias Pedersen, Breomy'nj': assignoretd American Machine and Foundry pamper-nae 1 l corporation ofrNewJersey App licationMay 24;1945; Serial Natds'nt? 1 This invention relates to-sewing machines and V moreparticularly to sewing machines of the over:

and under orrunning stitch' type which utilizes apairof opposed needle bars positioned onoppo-a site sides of a-work supporting -table,-*-and provided-with means for gripping and =proj ecting a double pointed "needle having an eye located be-= tween itsi ends and'a thread back 4 and forth'. through material to besewed.

Infltheoperation ofthis type of: machine it has been found that becauseofdifferences in the characteristics of" the types of thread available;

it is difiicult to always insure that the-thread will: be properlypositionedw with -respect td the instrumentalities of the machine which coactrwith the needle: bars the J needle -'.and1 the/thread ahandling elements in handlingithe rthread ion-proper sewing without breakage iof the thread or the ne'ed1e=or both during ope'rationi of; :the machine:

With some kinds. ofosthread there is "little or no" troublei in' ithe; rzop'er toperationa of; the machine;

cottonzlthread, and substitute threadsnowavail-x able, it ha'se beencifoundaz that in the: formation: of. loops above andzrbelow 1 the work supporting: table thererisa tendency for the thread tocurllaround the needle' or formnirregularloops which arepo-l sition'ed out ofxth'e paths a of 1 traveluofic the looper and .theflthread puller; respectively; These .un-'

satisfactory characteristicsaof; thewthread cause improper operation of the machine and thread and needle breakage; The mechanism :comprising-the present invention makes possible the use ofw substantially any :kinduof thread with a, minimum' of stoppage; or breakage ofv, thread onnee- Work table and pulls the, loose end'of/the thread over thelooper and through the work.

thethread and below- -the workare not properly disposed in plajnes substantially atrightangle to the path oft-movement of thellooper andithe" threaiiQpulIe'r; the looper will =be unable-i'towengagethlfloop of-ilthread above the work erovmexsn'cam. the

thread and. support the engaged portion of the 20 caims. 1 (01. 112911 1 )1 thread during theoperation20f. thesthread puller. So' also the thI'EQId DUHEI WHLIIOt be able to en-' gage a pol tion of the 100pl beneath the work table inorder topu1l; the? loose end of the thread over the looper and through the'owork; A V

"Accordingclto imyxinvention :there. are provided device's which lcooperateowith the looper and the thread: puller; fortinsuring: that each loop formed willxbe: properly.positioned and so held with respect to the paths of motion of. the looper. andthei ithreadi puller lthafij at all times that portion of:.each.loop of threadxiwhiclr is to; be engaged by thenlooper and theiythread puller is so engaged withgtherresultthat: the operational? the-machine: is effected withoutinterruptionorrthread or nee.-;

dle breakage;

The mechanism ofi the present invention relates to improvements for use on a sewing machine of the generaltype disclosed in Johnson Patent No. 2,368,066, issued January 23, 1945, and

Johnson goo-pending; application, Serial 1N0. 355,738, filed September 7, 1940, for Sewing Machine, now Patent No .t2,386,800, issued October 16;;1945l Although this-mechanism is designed breakage. v

It is a further object of my invention tolpro-. videla .loopnengaging. member. coacting with the IOop'er OfJa sewing vmachine having opposed a1; ternately"reciprocating needle bars which project a double pointed; needle andathread having a loosefandla fitted endback and forth" through worklto be sewed inorder to'insure that on each operation a of the .ljooperl I a, predetermined portion of a loop of" thread will be engaged and properly handled? V It isa' furtherobjectfof my invention to pro ride a loop disposing; and positioning mechanism coactingwith" theilower ,needle bar of a sewing machine oiithe type described which functions to" engagef-and fstabili zeLthe position of a loop ofg'th'readlformedby the operation of the lower needl .bar in order to .insure that the thread puller "will engage a predetermined. poreonor a lgop of thread duringreachfcycle ofFits operation. It is'afurthe'r object army intention toprovide thread loop stabilizing and positioning mechanisms which coact with the thread looper operative adjacent the upper needle bar and the thread puller operative adjacent the lower needle bar of a machine of the type described herein and which function to maintain predetermined portions of loops of thread properly positioned with respect to the paths of motion of the looper and the thread puller so that at all times during the operation of the looper and the thread puller the loops of thread are engaged by these elements.

With these and other objects notspecifically mentioned in view, the invention consists in certain combinations and constructions which will be hereinafter fully described, and then set forth in the claims hereunto appended.

In the accompanying drawings, which form a part of this specification, and wherein the several reference characters designate the same or like elements:

Figure 1 is a partial assembly view, partly in section, showing the relation between the needle actuating bars, thread handling mechanisms and the loop positioning and stabilizing mechanisms forming the invention;

Figure 2 is a side view showing diagrammatically the upper loop positioning mechanism in operative relation with respect to the looper, and the lower 100p stabilizing and positioning means in inoperative position;

Figure 3 is a similar view showing the position of the lower loop stabilizing and positioning mechanism in operative relation with respect to the thread puller which is about to engage a properly positioned loop of thread;

Figure 4 is a front view illustrating somewhat diagrammatically the manner in which the upper loop positioning mechanism coacts with the looper shortly before its engagement with the looper; Y

I Figure 5 is a plan view Figure 2;

Figure 6 is a diagrammatic sectional perspective view illustrating the lower loop stabilizing and positioning members in operative position and some of the operating mechanism therefor; and

Figure '7 is a diagrammatic plan view partly in section showing the mechanism illustrated in Figure 6 at a later stage in its cycle of operation. Referring to the drawings, in Figure 1 there is shown a partial assembly'view, partly in section disclosing the general structural and operative relationship between the mechanism constituting the invention and a sewing machine of the type shown in the above referred to Johnson Patent No. 2,386,800. I

The machine is provided with a center support frame 30 and a combination end frame and housing 3i, the frames being secured to and spaced from each other by suitable supporting members (not shown) which in turn are secured to the pedestal of the machine (not shown). A work supporting table 35 is suitably attached to a bracket (not shown) which in turn is secured to the machine frame in any desired manner. 7 The drive of the machine is effected by a pulley 3! driven by a belt 38 which also runs over a taken on line 5-5 of .pulleyinot shown) integral with a suitable clutch driven'from a motor (not shown) in the same manner as disclosed in Johnson Patent No. 2,368,066. Since this mechanism forms no part of the invention, further detailsa're omitted in the interest of brevity. g

Pulley 3'! is secured to the hub 46 of a gear the ends of arms 66, 61.

4| rotating about a stationary stud 42 fastened to the wall of frame 3| by screws 43. A hand wheel 44 secured to pulley 3'! is'provided to permit manual turning of the machine. A cam 39 is formed integral with and on the inside face of pulley 31. Cam 39 is provided with a cam track 45 engaging cam followers 46, 47 positioned at diametrically opposite points of the cam and mounted on arms 48, 49 formed on the rear ends of oscillating levers 56, and 5|. Levers 50, 51 are pivotally mounted on shafts 52, 53, respectively, shaft 52 being supported at one end in a hub 54 of a bracket 55 secured to wall member 3| and at its other end being supported in a lug 56 secured to a bridge (not shown) of frame 3|} One end of shaft 53 is supported in a hub 58 of a bracket 59 fastened to frame 3|; its other end is supported in a hub 6 of a bracket 6! suitably attached to member 3|.

An upper needle bar designated generally 63 and a lower needle bar indicated generally 64 (Figures 1, 2, 3, 4 and 6) arranged in opposed axial alignment on opposite sides of work supporting table 35 are provided with actuator members 65 connected to extending arms 66 and 61 at the forward ends of their respective oscillating levers 50, 5| whereby to convert the oscillating motion of levers 50, 5| into vertical reciprocating motion of the needle bars back and forth relative to table 35. The upper needle bar 63 is guided in bushings carried by lug l0 suitably attached to the forward end of the machine frame 3!. The lower needle bar 64 is guided in bushings formed in lugs 12, 13 suitably supported on the machine frame 3|.

The actuator members 65 are held in lace on the respective needle bars 63, 64 by suitable lock nuts 15 (as shown in Figure 1). Vertically extending portion 16 of each member 65 is provided with a track 11 in which slides a rectangular block 18 carried by studs (not shown) fixed on The sliding blocks 78 provide means for converting the oscillating motion of arms 66, 61 into the desired vertical reciprocating motion of needle bars 63, 64.

The needle bars are similar in construction to those disclosed and described in co-pending J ohnson application, Serial No. 448,189, filed June 24, 1942, now Patent No. 2,402,251, issued June 18, 1946. Each needle bar 63 and 64 is provided with a suitable chuck including needle grippers and operating mechanism therefor for grasping and releasing one end of a double pointed needle at the proper time during the operation of the machine. Since the specific construction of the needle bars forms no part of this invention, further details and description is considered unnecessary.

It will be understood by those skilled in the art that in this type of sewing machine the needle 8| is alternately grasped in the chuck of each needle bar. The action is such that as the lower needle bar 64 projects the needle upwardly through the work, it passes through an opening in the lower end of the shell 9i of the upper needle bar 63 a predetermined distance. In the continued operation of the machine, the end of the needle gripped by the lower needle bar is released and the upper end of the needle is gripped by the upper bar 63 and pulled thereby through the work. On the next downward movement of the upper needle bar- 63, the point of thelneeclle being projected downwardlythrough the work to form the next stitch is passed through an opening in shell 9| of the lower needle bar thereby,- after itis released trorn the upper"needle Fba'r.

:Work feeding 3i and -press er room mechanism of thei-same general-type as that showm in the: above referred to patent; NOJ2,3865800, can be used \f or aeytaaoai the upperrneedlegban 3,\as indicated in Figure 8.

feeding 'thegworkalong the table 35 and past the needle 8I. This -mechan-ism: can-consisthf-=a work feeding t bar I23 provided with a feeding dogi Ii22omounted for movement in: asclosed tunidirectional rpathhbeneath the work :table35 Rand projecting upwardly througheanmelongated aperture inLthe table "35.into cooperating feeding engagement with a presse-r foot I28 andwan .upper zwork: feeding foot. 12 I constructed. and operated the same manner as disclosed in PatentpNo.

2386;800. msinceizthetspecificeconstruction of this mechanism form noipartiof: the invention; turather: detailed description" and shoiwinguis deemed :unnecessary. As inentioned' hereinabove, apulley -3'Iz1isfdrivengby mean ofa beltg38 .running over sca'iclntch :(notshoWn). I l \Iniorder to operate the machine and drive .pulvley,v3l'l ,wthere is? provided a manually operated trea'dle (not shown) similar to that shown in 1 :the :above referred to Johnson 1 Patent "No. 2,368,066 for transferring. the driveirfromrthe moirtorito pulley .3I,.and hence. through the. gear; train ;I I 226,'%229, ,23I.and r232; driving the several rinstrumentalities described hereinafter. Arman- .ually operated treadle (not shownkmay also be ::.employed for raising ;;and lowering :the rpresser foot 1-20 in order to position workvlforisewingio removal from table 35.

513A looper cam I (Figurell) .securedjtothub 401 istracked by a cam follower I'II which is mounted; onastud I'I2 carried by a lever I'I3secured to a cross shaft I14 suitably mounted at V "one end in frame 3|; and itslother end ingalhub j; I 19 of a-bracket (not shown) 1 fastened; to. 13;; por- :1

n n 't d e se t n i thema h qframecam fo'llower 1| II-is held, in engagement with gam I!!! by means of a sprin llfiv'Wl'liChiS stretched gb tween a post IIB-inj lever I13 and a post-gtnot tsho w n' fextending :from housing ,3I. I

Secured to shaft I14" adjacent and-in front of uthesupper lneed-le-bar 6,3 is;a lo per-arm I8I proyided rat its lower end with a pointed-finger or rshoe I82 and a thread guidesroller I831which' together with a; tension? finger x184 mounted as cja-centrthe upper needle :bar and substantially; at the opposite .side thereof with respect to clooper tinues totravel-until the point: of finger I82 is about ani alig-nment with the tip of finger 184cm which position-it dwells'momentarily. :Continued rotation of cam 39 Land the coaction between cam -and cam follower 46 on arm .48 causes the needle barcfii to descend slightly and dwell and in so doinga loop is formed in the thread; -Substantially simultaneously arm 1I8I under the ac- V tuation of cam I10 and finger I84 advance-in unison in -a clockwise direction; shoe I82 on arm I BI engages the front portion L1 of the loopvin the-: thread (Figures 4 and 5) While finger I84 engages the rear loop portion L2 (Figures 2, 4 and 5). As shown in'Figure 2, finger I84 comes to-r'estwithloop portion L2 displacedout of the path of travel of theneedle BI, and any'danger of splitting" or damaging by the needle of that portion of-the thread is substantially: eliminated. Looper arm I8I continues to move in aclockwise direction'and the portion L1 of the loop which has been guided by shoe I82 onto roller-I83 is displaced to substantially the position illustrated in FigureZ whereupon the upper needle bar 63 completes-its v downward stroke and'delivers the needle to the lower needle bar 84;

Continued rotation otcam I'll! causes the looper arm I-il I to move in a counterclockwise direction towards up-per needle bar-$3 where it dwells insubstantially -the position shown in Figure 3 during the formation of the next-loop beneath the-work and the pulling of the loose I end-of the thread over rol leral83 andl through the work'in completing the stitch'. The-forward advance or clockwise movement of finger I84 is stopped when pin I9 abuts stop-screw ISlladjustablymQunted in-w'ing' V I82 ofvholder-r83suitablyfastened toframe-member II while at the same time the looper arm I8I is operating as described above -Upon-com-' pletion o'f' the operationof "the thread puller 282 inpulling the loose end ofthe-thread-through the work, the'looper arm I8I and the finger I84 are moved counterclockwise to their inoperative positions where they remain pending the next .tdownward movement of the upper needle bar63.

During the: operation of this type of machine,

there is a tendency for loop portions L1 and L2 of the upper sloop-and portions L3, L4 of thelower .looptovcurl about the needle" 8|. in 'such away i that these loop portions are not DIODBIIY LDOSiationedfinthe path or travel of shoe I82 on looper armrl 8 Isorfingerl 34, or thread puller 282. When a loop portion :of 'ther thread is not properly disposed and supported with respect tothe fneedle or the "thread handling-.elements mentioned, breakage of the thread orthe needle or both --may take place;

In order to overcome such undesirable features, which result-in loss of time, machine stoppage;-'and replacement of needles, there are-promally heldrinoperative by a stop screw I90 adapted vdisengage a pin I8I projecting from arm I85,

yscrew-I-IQO being adjustably fastened in a wing .I92 of'aholder -I93-secured to member 7L, formiqing'a part of the bridge frame (notshown).

When the needle is transferredfrom the-lower needlebar-M to the upper needle bar 63, the

latter grasps-the needle-and duerto the continued rotation of cam 39 and the'actuation of lever 58' moves to its up-position. The looperarm I8I by a means of its cam I10 is moved counterclockwise v (as shown in Figures "2"and'3) towards finger 184 which normally ispositioned to :the -right of vided 'th read stabilizing and positioning mecha- I nisins fwhich co-act with the upper and lower needle bars and thread handling elements and makepossible the use of all kinds'ofthread'with a minimum of-breakage of thread or needles.

' The mechanism which coacts with the upper needle bar andthe-looper I8I and finger I84 is designated generally I5 9 and consistsof a lever I8I] pivotally' supported on apin I62 mounted in an extension I63 "formed on looper arm] 8 l Lever 168 is {provided with a flat plate I64 extending 'at an angle to the lever as shown in Figure 4.

A relatively light spring! 66, positionedabout pin -I BZ-andprovided with an end 1 6-1 bearing against Figure 2 or occupies a dwell position to the left .of needle 8i, as viewed in Figure 2, spring I66 holds plate I64 against stop I8Ia on looper arm ,I8I. However, when the upper needle bar 63 :has moved downwardly to the position shown in Figure 4 and formed theloop having 100p porstions L1, L2, plate J64 will operate in conjunction with the. needle to form a, support for these ploop portions and prevent them from curling :around the needle. In other words, plate I64 :tends to maintain loop portions L1, L2, in a plane ;substantially at right angles to the path of movement of shoe I82 on looper arm I8I so that as the looper'arm' I'8I swings or moves in its clockwise direction, loop portion L1 is always posiationed directly in the path of movement of shoe I82, and loop portion L2 is locatedproperly for :engagement by finger I84. Movement of looper earm I8 I ina clockwise direction beyond the path :of movement of needle 8! through the work, :makes it possible for spring I66 to swing plate I64 111130 a position closely adjacent or in engagement with the pointedend of shoe I82 so that lateral movement or escape of the loop portion L1 from .roller I83 is substantially prevented. Plate I64 is of alength sufficient to provide support for loops L1 and L2, and prevent substantial twisting thereof out of the paths of shoe I82 and finger I84 regardless of whether. right or left twist thread is used.

In the illustrated embodiment, the relationship rbetween the-end I8Ia of arm I8I and plate I64 is such that as the looper shoe I82 moves past needle 8| and plate I64 is moved by spring I66 towards shoe I82, plate I64 engages the end portion I8 I a. of the arm IBI, acts as a stop and holds plate I64 a short distance away from the pointed end of shoe I82. This prevents a rapid move- -ment of plate 64 against the end of shoe I82 -which might result in breakage or a pitting of the plate. r The operation of looper arm I8I and finger I84 as mentioned above is the same as the operation of like elements disclosed in the above referred form-a loop in the-[thread with'loop portions L3,

L4 disposed somewhat as shown in Figure 6.

Figures 1, 3, 6 and '7 show the thread loop stabilizing and positioning mechanism for insuring that loop portion L3 is always maintained in .a plane substantially at right angles to the path r-Of movement of the thread puller 202 so that in each cycle of operation of the thread puller 202, .loop portion L3 is so located with respect to the thread puller that it is always engaged and the .loose end of the thread pulled through thework land disposed about drum 309. r The thread puller 202 which is operated in so'jthat :during the rotation of gear 232 rotary motion is imparted to arm 246. The movement of-thread puller 202 carried by arm 246 is such that as the puller 202 advances its forward pointed end engages the positioned and supported loop portion L3 formed in the thread (Figures 3, 6 and 7). Thread puller 202 moves slowly into engagement with loop portion L3 as it starts to pull the loose end of the thread through the work. It'will be seen that thread puller 202 does not act with such quickness in starting the pull :iof. the thread through the work so as to tend to fray out the thread after a'number of pulls or witha'tendency to jerk and break the thread. However, after the pull is actually started, the movement of arm 246 and puller 202 increases speed when danger of thread breakage is passed. The action of the thread puller, therefore, is to pull the loose end of the thread through the work with gradually increasing speed from approximately the time it first picks up the thread loop portion L3 and as it travels with the thread to dispose it about drum 309. The construction and mounting of arm 246, puller 202 and drum 309 are the same as disclosed in Johnson Patent No. 2,386,800, and further detailed description thereof is deemed unnecessary.

5 'A 'tensioning finger (not shown) coacts with the thread puller to dispose the thread properly out of the path of the needle so that at the time of transfer of the needle from needle bar 64 to needle bar 63, the thread is held out of the path of the needle 1 and properly tensioned. This -mechanism forms no part of the present invention and further description and showing thereof is not considered necessary.

Operating in conjunction with the thread puller 202 and drum 309 is a thread trap 306 and a pair of laterally movable gripping jaws 288, 289 which engagethe thread, move it laterally 0r 'rearwardly (as seen in Figure 2) to position a portion of the thread in the trap 306 out of the path of the needle and the moving thread puller. Thismecham'sm, which is the same as that disclosed in the above mentioned Johnson Patent :No. 2,386,800 is not shown or described in greater detail :because it forms no specific part of the present invention.

' In order to prevent excess tensioning of the fixed portion of the thread in the work during the operation of the thread puller 262 there is provided thread gripping mechanism similar to that shown in the above referred to Johnson Patent No. 2,386,800. This mechanism consists of gripper {arms 200, 20I operated by a cam 203 fixed to shaft {205 driven by a gear 226 fixed thereto meshing -with gear 229, which gear in turn meshes with gear 23I. Cam 203 has a cam track I in which runs a cam follower 206 on a cam lever 207 mounted on stud 208 carried by a holder 209 fastened to support 2I0 attached to frame 36. The upper end-of cam lever 26! is provided with an open end yoke 2II adapted to engage a block 2I2. pivoted in a bar 2I3sliding in block member 2 I 4 suitably secured to the frame of themachine. 1 Gripper jaws 200 and MI are mounted for pivotal movement on pins 2 I6 in block'2 M; the jaws are :provided with extensions 2I9 in which are 9" mounted; cam! followers camta trackss 215' formed in slide member .12 [31's It will be seen: that theo'rotationof vcam 2032 causes at:

. alwaysvproperly' positioned and": maintained in;

proper location forv engagement by threadqpuller 2ll2ythere is provided a pair of clamp; members orplates 250 ipivotallyrmounted on pins '2 52 fixed in drum305 (see Figures 1, 6 and 17). Plates 250. are, provided with: downwardly extending angular: projections 251 which "are'engaged: by the:tipsl 22ml otlgripper: jaws 200, 20 l r so; that :as the jaws :open. or :move to inoperative" positions-the; plates are also openedyand moved toathespositions.indicatedr in dotted .lines inJFigure; 'lpin .orderfto .allow the lowerineedle bar 64 to continueitsupward movementzand: project .the needle :81; through theuworkj and deliver it to the uppenneedlzbar 6-3. Angular: abutmentsjzfid formed onthe.rearlfacesot-plates 25tllimit the, extent of opening" movement; of, plates-250. Aspring 253ihaving its ends secured toiplates 250;maintain.pro;iecti'ons '25l in engage 211 which aretlocated; in;

ment'with grippervjaw-Vtips 2H,. and surge the I I plates 25fl -is suchlthatvplatesafifl reach their closed thread loopstabilizing position, as shown infull lines Figurefl, inadvance of, grippenjaws .200,2 U|.;" r i In order to control the inward movement of plates 250- by spring- 253 to their loop holding positions (Figures-6 and: 7);, and prevent damageg thereto by striking-againstthe needle such as the formation of grooves in those portions; of the plate which move into adjacency; with thevneedle there are provided collars 260;- having flat faces. 262, adjustably mountedon pivot pins-252 and secured in adjusted :positionsb set screws .264;-

1 Collars 260 'can'be so adjusted. (asrshown in Figurer 7) that portions thereof project outwardly beyond plates 250 andvact asstops tohold platess- 250';

spaced apart relative toneedle '8I. Therefore;

in Figures-6 and '7 ),-rtherescanw be free upward g when plates. 25011arein closedaposition- (as shown movement of needle ill therebetween and. the; V

proper formation of lower loops'--having portions? L3; L4.- 7 Y The-"timing of: the machine.-

such'uthat camsv 2U3-causes cam slide 24 3tobegin the movement of; jaws'2il0; 201 during the final downward movement of needle: bar-e3fandv asythe' needle Skis:

transferredsto lower'=needlebarr64', slowly into closing or thread-gripping" position: This 013- tion as limited :iby collars i 2 6 fliprior; to: the 1 next; upward movement: OfTlOWBITL'IlBBdIBI bar: '6 mend needle 81: Therefore; ZSthEii'llGf-Jdlfi? moves: up;

wardlyst'o form a lowerrloopg' itipasseshbetween' therclosed plates 250 3111d17h6'JOOPZPOIfbiOIlSFLa and? L4 :which extend-outwardly from-the needle, are formedandrpositioned ibetween plates .250'in the.

manner shown; in Figures, 6 ands: 7 Because of: this association-theloop portions L3; L4 airestabil 126d? and held properly-1ocated betweentheplates 25D-rand cannot twistang'ularly aboutitheneedle 8 leasw it moves-upwardly between the plat-es? Bee fore the loop pontiornLs-fis' completely iormedither movement of. slide 2 3 by-scam zcs is' completedl and-gripper jaws 200,-20l closeagainst and grip loop portion L4. Continued upward movement of the-needle bar 64 causesa further expansion of loop portion L3 to the position indicated in Figure Balthough'if desired the timing can be such that the-loop portion L3' is completed formed before that each is located properly directly in the path of'thamovementof the thread puller 202'; for on gagement thereby, which is then moved b'ymech anism? described 'hereinabove into engagement with loop portion' Ls and pulls-the loose endro'f the thread overtroller I83; through the work and' la-ys'it upon drum 309 in known manner; The" upper surfaces of jaws 200,*2lll"are' reduced-in anamount substantially equal to the thicknessof l plates inorder that the plates :may lie flush 'in construction:Within-the scope" of the claims,

forthe particularfdevice, selectedto illustrate" the inventionfis but one 0f-many possible concrete embodiments of the same. 'It is'not, therefore; to

be restricted 'to the: precise details of'the structure-shown: and described. What I claim: is! I. Ina sewing machine provided with a needle bar and aneedle'for'projecting'a thread throughmaterial to be's'ewed', mechani's'mrfor moving said" bar 'to and from said-work, a -thread'looper armmounted: adjacentsaid bar; alooper: on said arm adapted 'to :engage aloop formed in said thread;

and a *membermarried by said arm being constructed. and :arrangedto coa'ct'withsaid needle for positioning saidrloop for engagement by said looper. r v

2. In? a sewing machineprovided witha work supporting table; awneedle' bar and'a needle for projectingca thread throughmaterial to be'sewed',

mechanismfonmovingrsaid bar"tow'a-rds said Inat'eria land forming a loo'p'rin a portion ofr'said thread, a looper' arm, a: looprengaging shoe car 7 ried' by said arm; and a resiliently mounted loop positioning member constructed and arranged:

to r cooperate with said ineedlecarried bysaid arm; for maintaining saidloop positioned in the path of-movement ofzsaid's'ho'e for engagementthereby;

3; In a -sewing' machine provided with a work supportingtable, a-- needlebar :andj a needle for projecting a thread-through material tobe sewed,

mechanism; for moving 'said'bar towardsisaidi material and forming a loop a portion of saidthreadi'z a looper; 'a loop' positioning-member car= ried: b'y "said' l'ooper constructed-and arranged-to cooperate with said needle for maintaining -said% loop positioned' for engagementbysa'id looper';

said membercomprisingqa-lever provided, with a taining said loop positioned for eng'agementby' said shoe, said member comprising a movable loop positioning'plate, a mount on said arm for said plate, and means for moving said plate into operative relationship relative to said shoe.

5. In a sewing machine of the type described having a work supporting table and a'vertically' reciprocable needle bar mounted for movement to and from said table for projecting a needle and thread through material to be sewed, a thread engaging finger movably mounted adjacent one side of said bar, a looper mounted adjacent another side of said bar, mechanism for reciprocating said bar and forminga loop in said thread above said table as the bar and threaded needle travel towards said table,'means for moving said finger to engage one portion of said loop, means for moving said looper to engage another portion of said loop, and a device constructed and 'arranged 'to cooperate with sai needle for posi-' tioningsaid loop in the path of movement of said looper.

' 6. In a machine of the type described having a work supporting table and a reciproc'ableneedle bar'mounted for movement to and from said table" for projecting a'threaded needle through material to be sewed, a thread engaging finger movably mounted adjacent one side of --said'bar,

a' looper'mounted "adjacent an oppositeside of said bar, mechanism for reciprocating said bar and forming a loop in said thread above said table on each movement of said threaded needle towards said material, said loop having a rearpor- 7 tion and a front portion extending generally'i'n' a' plane substantiall'yat right angles to 'the path of movement of said material over said table, means for moving said'finger to engage and displace said read 'loop relative to said needle, meansfor movingsaid looper, and a device mounted on said, looper constructed and arranged to cooperate with said needle for holding said front portion of said loop in position to be engaged by said looperQ 7. The structure defined in claim 6 wherein said device comprises a. movably mountedlever, a loop eng-agingplate'on said lever, and resilient means for biasing said plate towards said looper;

8. In a sewing machine of the type provided: with a work supporting table and opposed needle bars mounted on opposite sides of said'table,

mechanism for reciprocating said bars alternately to project a double pointed needle and a thread back and forth through said work to form stitches in said work and alternately form loops above'and below said work a thread looper mounted above said table, a device constructed and arranged to cooperate with said needle for maintaining loops in said thread above said table position to be engagedby said looper, loop positioning means mounted beneath said table, a thread puller for engaging loops formed in said thread beneath said table ,andmaintained in the path of movement of said puller, and mechanism for operating said said table, a loop positioning device mounted on said looper, constructed and arranged'toposition asasgom a portion ofa loo'pabov'e said work in the path of said looper, a thread puller located beneath said table, and loop positioning means coacting with said puller for positioning a portion of a loop formed beneath said table in the path of said puller for engagement thereby.

l0. In a sewing machine of the type defined having opposed alternately reciprocating needle bars, and mechanism for alternately moving said bars to project a threaded-double pointed needle back and forth through work to be sewed, a looper mounted adjacent one of said bars, a thread puller mounted adjacent said other bar, a loo-p positionin device to position a loop formed by the movement of one of said bars in the path of movement of said looper for engagement thereby, a second loop positioning device mounted adjacent said other bar, and means for operating said second device to'rnain'tain each loop formed by the movement of 'said second bar in the path of movement of said puller.

1'1. Ina sewing machine provided with a work supporting table and a needle bar, mechanism for reciprocating said bar to project a needle and a" thread having a loose and a fixed end through work to be sewed and to form loops in said thread, 'a thread puller, means for engaging and positioning loops formed in said thread in the path of movementof said puller, and means for driving said puller to cause it to engage each of said positioned "loops and pull the loose end ofthe thread through the work.

12. In a sewingmachine of the type having opposed alternately moving needle bars for projecting a double pointed needle and a thread having a loose and a fixed end back and forth through work to'be sewed, a looper mounted adjacent one of said bars, a thread puller located adjacentthe other of said bars, a loop positioning member-constructed and arranged to support a loop formed in said thread above said work directly in the path of movement of said looper for engagement thereby, means for moving said looper into engagement with said supported loop to engage and support a portion of said thread, a loop engaging and positioning device for holding each loop formed adjacent said last-named needle bar in a plane substantially at right angles to the path of movementof said puller, and means for moving said puller 'into engagement with each loop supported by said device for pulling the loos'eend of said thread over said looper and through said work.-

13. In a sewing machine of the type having opposed alternately moving needle bars for pro jecting a double pointed needle and a thread having a loose and a fixed end back and forth through work to be sewed, a looper mounted adjacent one of said bars, a thread puller located adjacent the other of said bars, a loop positioning member constructed and arranged to support a loop formed in said thread above said work directly in the path of movement of said loo-per for engagement therebyymeans for moving said looper into engagement with said supported loop to pull and support a portion of said thread, a pair of pivotally 'mounted thread positioning jaws for engaging i and positioning each loop formed adjacent said'las'tnamed needle bar in a planesubstantially perpendicular to the path of movement of said puller; a pair of gripper jaws for holding the fix'ed end of said thread against excess'tensioning in said work during the operationing jawsfand said gripper jaws 'for closing jectinga double pointed needle and a thread having a loose and a fixed end back and forth through work to be sewed, alooper mounted adjacent one of said bars, a thread puller located adjacent the other of said bars, a loop positioning member constructed and arranged to support a loop formed in said thread above said work directly in the path of movement of said looper for engagement thereby, means for moving said looper into engagement with said supported loop to pull and support a portionof said thread, a threadreceiving drum,a pair of thread positioning jaws for engagingand positioning each loop formed adjacent said last-named needle bars in a plane substantially perpendicular to the path of movement of said puller pivotally mounted on said drum, a pair of gripper jaws for holding the fixed end of said thread against excess tensioning in said work during the operation of said puller,

connections between said positioning jaws and said gripper jaws for closing said first-named jaws on said loop prior tothe closing of said gripper jaws on said fixed end of said thread, and means for operating said gripper jaws.

' 15. Thread loop positioning mechanism for a sewing machine having a thread supporting drum, opposed needle bars for projecting a needle and a thread having a loose and a fixed end back and forth through work to be sewed, comprising @a pair of movably mounted thread engaging 16. Thread loop positioning mechanism for a' sewing machine having a thread supporting drum, opposed needle bars for projecting a needle and a thread having a loose and a fixed end back and forth through work tobe'sewed, comprising a pair of pivotallymounted thread engaging, plates supported by said drum, a thread puller, mechanism for reciprocating said bars to project said needle and thread through said work and form a loop in said thread during a portion of the operation of said mechanism, a thread puller, means operative after the formation of each loop for closing said plates against said 14 sewing machine having a thread supporting drum, opposed needle bars for projecting a double pointed needle and a thread back and forth through work to be sewed, a pair of plates movably mounted on said drum, spring means normally urging said plates towards each other, thread grippers, mechanism for alternately reciprocating said bars and forming loops in said thread first on one face and then on the other face of said work, operating means for said grippers,and connections between said grippers and said plates for effecting a movement of said plates 'against opposite sides of a loop in advance of the gripping of a portion of said loop by said grippers.

18. In a thread loop positioning mechanism for a sewing machine, a thread supporting drum, means for forming a loop in a thread adjacent said drum, a traveling thread puller adapted to engage a portion of said loop, thread loop engaging and positioning members, and means for effecting movement of said members intoengagevment with said loop to position said loop in a plane substantially perpendicular tothe path of movement of said puller.

19. In a sewing machine provided with a work supporting table and a needle bar, mechanism for reciprocating said bar to project a needle and a thread back and forth through Work to be sewed, said mechanism being operative to form loops in said thread spaced from the surface of said work, a loop engaging device having a path of movement into engagement with said loops, means'for engaging opposite sides of said loops and positioning said loops formed in said thread in a plane substantially perpendicular to the path of movement of said device, and'means for operating said device to cause it to engage said positioned loops.

20. In a thread loop positioning device for a sewing machine having a work support and a reciprocatory threaded needle, means for forming a loop in a thread spaced from work positioned on said support, and having a, loop portion on opposite sides of said needle, a loop engaging member having a path of movement into engagement with said loop, means for engaging opposite sides of said thread forming said loop portions and positioning at least one of said loop portions in a plane substantially at right angles loop to hold said loop in the path of said puller,

and means for operating said puller for pulling the loose end of said thread through said work and disposing it upon said drum. V

17. Thread loop positioning mechanism for a tothe path of travel of said member, and means for moving said member to engage said loop portion of said loop of thread.

MATHIAS PEDERSEN.

REFERENCES CITED UNITED STATES PATENTS Name Date Brogan Sept. 30, 1919 Number 

